signal misc

signal misc

在user space注册信号处理函数

sigaction()函数prototype：

int sigaction(int signum, const struct sigaction *act,
struct sigaction *oldact);

    struct sigaction sa_usr;
    sa_usr.sa_flags = 0;
    sa_usr.sa_handler = sig_usr;
    
    sigaction(SIGTERM, &sa_usr, NULL);

在kernel space发送信号给user space进程

send_sig(int sig, struct task_struct *p, int priv)

sig即是signal num，比如SIGTERM，p是进程的task_struct，priv一般情况下传0即可